How do I organize passenger transportation?

Build residential districts in two different cities, and connect the two cities with a railroad. After that, enter one of the cities and press the icon over a residential district – passenger transportation will begin. You cannot carry passengers unless you have built residential districts.

If you want to send passenger trains to different cities at the same time, then you will need one more residential district for each new city and each new route. For example, if you want to carry passengers from Cross-Hill to Coldport and Highcloud at the same time, it means you should build two residential districts in Cross-Hill, because you are planning to open two passenger routes. But if you want to carry passengers first to one town then to the other you needn’t build two residental districts in one city - just two roads.